The invention relates to a safety filter for an outlying filter cartridge of hand-held vacuum cleaners. The filter cartridge is made of a rigid air-permeable jacket in which a filter bag made of paper is seated. If the jacket for this kind of filter cartridge is made of fabric and therefore not rigid, the jacket itself can serve as the safety filter. The jacket can be removed and cleaned for the situation that dirt escapes from the paper filter bag.
Filter cartridges can also be made of rigid air-permeable jackets made of non-woven fabric, for example. With such jackets, the foregoing is not possible because the jacket is stable as to its form and can only be cleaned with difficulty.